Research Circular #RS05-295 DATE: May 3, 2005 TO: Members RE: Riggs National Corporation ("RIGS/RNQ") Proposed Election Merger with The PNC Financial Services Group, Inc. ("PNC/WYL/VSM") FROM: Scott Speer Shareholders of Riggs National Corporation ("RIGS/RNQ") will vote on Friday, May 6, 2005, to approve a proposed Merger between RIGS and The PNC Financial Services Group, Inc. ("PNC/WYL/VSM"). If the merger is approved and consummated, the amount of PNC stock, cash, or combination of stock and cash to be received for each RIGS Common Share will be based on the average high and low per share sales prices of PNC Common Shares as described in the Proxy Statement/Prospectus and will be subject to prorations. The merger is designed to substantially equalize the value of the consideration to be received for each RIGS Common Share at the time of the merger, irrespective of the elections made by individual shareholders. The actual per share stock consideration and per share cash consideration to be paid to RIGS Shareholders will not be determined until the effective time of the merger or thereafter. The merger is expected to become effective on or about May 13, 2005. The Election Within the terms of the aggregate merger, individual RIGS Shareholders may: a) elect to receive an amount of cash ("Cash-electing"), OR b) elect to receive an amount of PNC Common Shares ("Stock-electing"), OR c) elect to receive a combination of cash and stock ("Mixed-electing"), OR d) register no preference ("Non-electing"). Non-electing Shareholders may receive only PNC stock, only cash, or a combination of cash and PNC stock. Cash will be paid in lieu of fractional PNC Shares. SHARES WHICH ARE NOT SUBJECT TO AN EFFECTIVE AUTOMATICALLY BE CONSIDERED "NON-ELECTING" SHARES. ELECTION WILL Elections must be submitted to the Exchange Agent: Computershare Trust Company of New York. The election deadline is 5:00 PM, Eastern Time, on May 5, 2005. RIGS Shareholders must observe all terms and conditions for the election as specified in the RIGS Proxy Statement/PNC Prospectus. Among such items, it should be noted RIGS Shares may be delivered pursuant to an election under "Notices of Guaranteed Delivery", which allows delivery of RIGS Shares within three (3) New York Stock Exchange ("NYSE") trading days of submission of the notices. Elections may be made under "Notices of Guaranteed Delivery", on or before the election deadline. RIGS CALL OPTION HOLDERS WHO INTEND TO #RS05-295 Page 2 PARTICIPATE IN THE ELECTION MUST EXERCISE THEIR OPTIONS IN ADVANCE OF THE ELECTION DEADLINE. In all cases, Call option holders exercising in order to obtain stock for an election must exercise in sufficient time to be able to make valid delivery pursuant of the election procedures. The Merger Consideration: Prorations The RIGS election will be subject to prorations as described in the RIGS Proxy Statement/PNC Prospectus. Because the election procedures allow for delivery of RIGS Stock under Notices of Guaranteed Delivery, the result of the elections may not be known until some time after the election deadline. Prorations cannot be exactly determined until after the result of the elections is determined. Accordingly, THE MERGER CONSIDERATION TO BE ACTUALLY RECEIVED BY EACH CATEGORY OF RIGS SHAREHOLDER (CASH-ELECTING, STOCK-ELECTING, MIXED-ELECTING, NON-ELECTING) MAY NOT BE KNOWN UNTIL SOME TIME AFTER THE SHAREHOLDER MEETING. THE FOREGOING IS AN UNOFFICIAL SUMMARY OF THE TERMS OF THE MERGER, PREPARED BY CBOE FOR THE CONVENIENCE OF ITS MEMBERS. CBOE ACCEPTS NO RESPONSIBILITY FOR THE ACCURACY OR COMPLETENESS OF THE SUMMARY. MEMBERS SHOULD REFER TO THE RIGGS NATIONAL CORPORATION AND THE PNC FINANCIAL SERVICES GROUP, INC. JOINT PROXY STATEMENT/PROSPECTUS DATED APRIL 6, 2005, FOR THE AUTHORITATIVE DESCRIPTION OF THE MERGER AND ALL OF ITS TERMS AND CONDITIONS. Contract Adjustments Pursuant to Article VI, Section 11, of OCC's By-Laws, all outstanding RNQ options shall be adjusted as follows. On the business day immediately following the Effective Time of the Merger each adjusted Riggs National Corporation contract will require the receipt or delivery of: the appropriate amount of cash (if any), shares of The PNC Financial Services Group, Inc. ("PNC") Common Stock (if any), and cash in lieu of a fractional share of The PNC Financial Services Group, Inc. ("PNC") Common Stock (if any), where such amount of cash (if any), The PNC Financial Services Group, Inc. ("PNC") shares (if any), and cash in lieu of a fractional The PNC Financial Services Group, Inc. ("PNC") share (if any) is based on 100 times the Merger Consideration per RIGS share to be received for a Non-Election, where cash in lieu would be paid for a fractional share of The PNC Financial Services Group, Inc. ("PNC") Common Stock, if any. Premiums for the adjusted RNQ options will continue to be calculated on the basis of a multiplier of 100, i.e., for premium and strike-price extensions, 1.00 will equal $100. The Riggs National Corporation option symbol will change to RKC. [Any FLEX series that may exist will be adjusted in a similar manner to the standardized option.] Adjusted Option Symbols On the business day immediately following the Effective Time of the Merger, trading in the RNQ option series will be on an adjusted basis. At 8:30 A.M., Chicago time, the following symbol adjustments to the options will be effected: #RS05-295 Page 3 EXISTING SERIES MONTH/STRIKE CALLS ADJUSTED SERIES* MONTH/STRIKE CALLS PUTS PUTS May May May May May 17 1/2 20 22 1/2 25 30 RNQEW RNQED RNQEX RNQEE RNQEF RNQQW RNQQD RNQQX RNQQE RNQQF -> -> -> -> -> May May May May May 17 1/2 20 22 1/2 25 30 RKCEW RKCED RKCEX RKCEE RKCEF RKCQW RKCQD RKCQX RKCQE RKCQF Jun Jun Jun Jun Jun 15 17 1/2 20 22 1/2 25 RNQFC RNQFW RNQFD RNQFX RNQFE RNQRC RNQRW RNQRD RNQRX RNQRE -> -> -> -> -> Jun Jun Jun Jun Jun 15 17 1/2 20 22 1/2 25 RKCFC RKCFW RKCFD RKCFX RKCFE RKCRC RKCRW RKCRD RKCRX RKCRE Aug Aug Aug Aug Aug 15 17 1/2 20 22 1/2 25 RNQHC RNQHW RNQHD RNQHX RNQHE RNQTC RNQTW RNQTD RNQTX RNQTE -> -> -> -> -> Aug Aug Aug Aug Aug 15 17 1/2 20 22 1/2 25 RKCHC RKCHW RKCHD RKCHX RKCHE RKCTC RKCTW RKCTD RKCTX RKCTE Nov Nov Nov Nov Nov 15 17 1/2 20 22 1/2 25 RNQKC RNQKW RNQKD RNQKX RNQKE RNQWC RNQWW RNQWD RNQWX RNQWE -> -> -> -> -> Nov Nov Nov Nov Nov 15 17 1/2 20 22 1/2 25 RKCKC RKCKW RKCKD RKCKX RKCKE RKCWC RKCWW RKCWD RKCWX RKCWE * Any additional RNQ series that are added prior to the effective time of the merger will also be adjusted in the manner described above. Settlement The OCC will delay settlement of the adjusted RKC option contracts exercise and assignment activity until the Exchange Agent determines the Non-electing merger consideration; the end of "when issued" trading in The PNC Financial Services Group, Inc. ("PNC"), if any; and until the determination of the cashin-lieu amount for fractional PNC shares, if any. GTC Order Conversion On the Effective Date of the Merger, immediately after the CBOE close, the system will convert or cancel all resting orders in the RNQ order book. If your firm has requested, all EBook orders (phone, wire, and electronic) and all ORS orders residing outside the book (booth or crowd routed) will be converted reflecting the adjustments. If your firm has requested, all EBook orders and ORS orders residing outside of the book will be canceled. If your firm receives EBook CXL drops, the CXL confirms will print at your booth at 3:15 p.m. ORS CXLs will also be transmitted electronically to your branches. Immediately after the close, the book staff will return a final written report listing the orders that are converted or canceled to all firms. If converted, this list will also show how the new orders will be adjusted. This report #RS05-295 Page 4 will be available on request anytime during the day prior to the night of the adjustment. Important Exercise Considerations After the merger is consummated and the contract adjustment described above is effected, outstanding adjusted RKC Call option holders will receive upon exercise (and Put holders deliver upon exercise) the aggregate Non-Electing merger consideration (on a per contract basis). IF RNQ CALL OPTION HOLDERS DO NOT WISH TO RECEIVE THE NON-ELECTING CONSIDERATION UPON EXERCISE AFTER THE CONTRACT ADJUSTMENT, THEY MUST EXERCISE IN ADVANCE OF THE CONTRACT ADJUSTMENT AND SUBMIT ELECTIONS PURSUANT TO THE ELECTION PROCEDURES DESCRIBED IN THE PROXY STATEMENT/PROSPECTUS. The election deadline is 5:00 PM, Eastern time on May 5, 2005. Exercisers must exercise in sufficient time, and observe all terms and conditions for making a valid election. Protect Provisions Until the contract adjustment is effected, exercises of RNQ options will continue to be settled in the regular manner, through National Stock Clearing Corporation ("NSCC"). Where an exercise is settled through NSCC, the rights of the exercising or assigned Clearing Member are governed by the rules of the NSCC. The Options Clearing Corporation (the "OCC") understands that the NSCC has rules or procedures designed to enable purchasers of stock subject to an election, tender, or similar event, to protect themselves for the value accruing to that event. These rules generally provide that persons effecting purchase transactions (including call exercises) on or before a deadline (including any election deadline) can be protected for the value of the event if Shares are not delivered to them in sufficient time to enable them to participate in the event, provided timely and proper notice of a participant's need and desire for protection is given to the NSCC. These rules are generally referred to as "protect" or "liability notice" procedures. Sellers of stock (including assigned call writers), who fail to make timely delivery to the NSCC, may be subject to liability under these procedures. Clearing Members should review these procedures of the NSCC to determine the appropriate timing for actions required to be taken to protect themselves with respect to the RIGS election. Specific questions as to these rules should be addressed to the NSCC. Special Risks CALL OPTIONS Writers of call options who are uncovered with respect to deliverable securities subject to deadlines or cut-off times (such as expirations of tender offers, rights subscriptions, elections, or similar events) should be aware of a risk associated with the timing of their possible assignments: Equity option exercise settlement normally occurs 3 business days after the exercise date, and 2 business days after the assignment date. An uncovered call writer who has an obligation to deliver securities in 2 business days of his assignment may not be able to fulfill his delivery obligation by effecting a regular-way purchase (3 business-day settlement) or call option exercise (3 business-day settlement after exercise). Such uncovered writer may #RS05-295 Page 5 nevertheless be subject to liability under the "protect" provisions of NSCC (see above) with respect to his assignment delivery obligation, because he cannot make delivery in 2 business days. Additionally, Cash Market (same-day, or less-than-3-business day settlement) may not be available, or may be expensive for buyers. PUT OPTIONS – Writers of put options should be aware that events such as expiration of election deadlines or similar events may have significant--possibly adverse-effects on the market value of the underlying security put writers would be obligated to buy if assigned as a result of an exercise done after the expiration of such deadlines, insofar as such securities would no longer be subject to elections, tenders, or similar actions. Questions regarding this memo can be addressed to Options Industry Services at 1-888-OPTIONS (1-888-678-4667). CBOE contract adjustment memos can also be accessed from CBOE.com at the following web address: http://www.cboe.com/ContractAdjustments